1. Field of the Invention
This invention relates generally to the modification of filamentous keratins, and relates more particularly to the modification and straightening of filamentous human keratins and compositions having ideal properties for such purpose.
2. Description of the Prior Art
The use of compositions to modify filamentous keratins such as human hair and wool has long been known. The known modifications of such filamentous keratins include, for example, the straightening of said keratins which are naturally wavy, frizzy, curly or kinky, and the conversion of naturally straight keratins to a wavy or curly state.
A typical example of the modification of filamentous human keratins or hair is the permanent waving of hair. It is well known that human hair can be set into a permanent wave by establishing a directed stress or deformation on the hair in the form of the desired wave, curl or other configuration, applying a reducing agent such as a solution of ammonium thioglycolate for a short time, rinsing out the reducing agent, and then treating the hair with a oxidizing agent such as sodium bromate solution or hydrogen peroxide. Many of the known procedures and compositions require the simultaneous use of heat with the waving composition, e.g., Oliva, U.S. Pat. No. 2,691,378, to cause or otherwise speed the permanent waving action of the composition.
During the initial treatment with the reducing agent, the natural stress in the hair is temporarily alleviated or minimized by the opening up of the cystine disulfide linkages found in the filamentous keratins. Upon oxidation, cystine bonds are again formed by closing of disulfide linkages, but now the closure occurs not with the original sulfhydryl groups liberated, but with those which have been brought into greater proximity as a result of the directed stress. The filamentous keratins reform, but they now retain the new waved structure as a permanent feature of the hair until either a new waving procedure is performed, or until the hair grows out.
The disadvantages of such permanent waving techniques are also well known, and include damage to the filamentous keratins and cuticles of those keratin filaments in the nature of loss of strength and brittleness, which in turn leads to difficulty in combing and breakage near the scalp; dryness and lack of lustre and sheen in the hair; inability to treat waved hair with other lotions and conditioners after waving; adverse affects resulting from the necessity of heating the filamentous keratins to produce waving; and the complexity of the procedures and compositions used, which comprise multiple solutions (reducing agent, oxidizing agent) which must be prepared and used in sequence, and which are often strong chemicals which must be carefully handled to avoid damage to the hair, scalp and hands of the individual(s) involved in the process.
Hair damage from permanent waving can, however, be somewhat ameloriated by the use of known conditioners, such as shown in Johnsen et al., U.S. Pat. No. 3,683,939, applied concurrently with the waving solutions or as a separate treatment.
Another example of the modification of filamentous human keratins or hair is the permanent straightening of wavy, frizzy, curly or kinky hair. The straightening of hair, however, in comparison with imparting a permanent wave or curl, is usually a more rigorous, severe process, particularly when permanent straightening of curly or kinky hair is required. The compositions known to the art for straightening usually comprise concentrated and dangerous reducing substances, particularly caustic soda or sodium hydroxide, to open up the cystine disulfide linkages in the filamentous keratins, which substances, if not used with extreme care, can severely damage and break the hair being treated, as well as burn the scalp of the individual whose hair is being treated. See, e.g., Calva, U.S. Pat. No. 2,390,073. As in permanent waving, permanent straightening compositions usually comprise multiple solutions, including a reducing agent solution and an oxidizing agent solution, and many of the known compositions require concurrent use of heat.
The disadvantages of the known permanent straightening solutions mirror those of permanent waving compositions, but are more magnified. Permanently straightened filamentous human keratins or hair is often severely damaged by the straightening process, suffering cuticle damage, loss of strength, and major breakage, both along the hair shaft and at the scalp line. Lustre, sheen, body and texture of the hair are very poor after use of conventional straighteners. It is also very difficult to straighten hair with the known compositions which has previously been dyed, tinted, bleached, double process bleached or otherwise treated, and any attempt to straighten hair immediately after bleaching or tinting with those compositions will result in severe breakage and damage. The complexity of procedures and multiple liquid compositions that must be used is also extremely disadvantageous, particularly as the strength of the reducing solutions is such as to hold out the potential for hand and scalp burns and injury. The strength of solutions used also requires careful control of contact time with the hair to prevent injury. With an individual with fragile hair or sensitive scalp, the known permanent straightening compositions often have to be removed before the desired degree of straightening of the hair occurs to prevent damage and burns.
A further disadvantage with known filamentous human keratin permanent straightening compositions is that the strength of reducing and oxidizing agents used renders unsatisfactory attempts to ameloriate hair damage by incorporating known conditioners into the straightening process, either concurrently with application of the reducing agent, or following application and removal of the oxidizing agent.
The optimum combination of properties for an ideal filamentous human keratins or hair modifying composition, particularly one useful for straightening wavy, frizzy, curly or kinky filamentous human keratins or hair, is such that:
(1) the composition must be sufficiently strong to effect any desired degree of modification or straightening without damage to the filamentous human keratins or hair, yet be in such form that it may be applied without injury to the skin or scalp of the individual whose hair is being straightened; PA0 (2) the composition must be usable on filamentous human keratins or hair previously dyed, tinted, bleached, double process bleached or otherwise treated, and be capable of causing the desired modification or straightening to such keratins essentially without damage or breakage; PA0 (3) the composition must obviate or minimize damage and breakage to the filamentous human keratins or hair, and must preserve and if possible enhance the strength, lustre, sheen, body and texture thereof; PA0 (4) the composition must be safe and easy to compound and apply to the filamentous human keratins or hair, preferably consisting of a single solution or composition which may be applied in one contacting with the filamentous human keratins or hair, must be effective without any necessary application of heat, and should require no after-treatment with a chemical neutralizer or conditioning composition; and PA0 (5) the composition must provide permanent modification, particularly straightening, of the filamentous human keratins or hair, said modification continuing without the necessity for additional treatment until a new modification procedure is performed, or until the hair grow out. PA0 from about 58 to 60 weight percent water; PA0 18 to 20 weight percent milk protein product; PA0 6 to 6.25 weight percent polysaccharide; PA0 5 to 6.5 weight percent sodium hydroxide; PA0 4.75 to 5.25 weight percent polyglycerol; PA0 4.75 to 5.25 weight percent aqueous collagen polypeptide/amino acid solution; and PA0 0.075 to 0.095 weight percent polysorbate-80.
None of the modifying compositions for filamentous keratins known to the art, however, particularly none of those known to be useful for the straightening of filamentous human keratins or hair, provide this optimum combination of properties desirable with respect to modification of filamentous human keratins or hair.